Preheat the oven to 230C/450F/Gas 8. Oil two baking trays and dust with icing sugar. Dissolve the yeast and a pinch of sugar in 150ml warm water and leave for a few minutes until the mixture begins to froth, then stir in the rest of the sugar and oil.

Combine the flour, salt and fennel seeds in a large mixing bowl. Dig a well in the centre and slowly pour in the yeasty mix, using a fork to incorporate from the outside as you go. When it has come together, use your hands to bring it into a smooth dough. Divide into 12 pieces.

Lightly dust a clean work surface with a little flour. Roll the pieces into balls, then roll out each ball until it’s about 10cm in diameter. Place them on trays, leaving a good amount of space between each.

Lightly brush the surface with egg white, then dust lightly with icing sugar and scatter over a little caster sugar (one creates the shiny surface, the other gives crunch). Bake in the oven for 10 to 12 minutes, until golden and crisp. Transfer to wire racks to cool.